Blue-red azo dye and process of making same.



UNITED STATES PATENT Qrricn.

ADOLF ISRAEL AND RICHARD KOTHE, OF ELBERFELD, GERMANY, ASSIGNORS TO THEFARBENFABRIKEN OF ELBERFELD COMPANY, OF NEW YORK.

BLUE-RED AZO DYE AND PROCESS OF MAKING SAME.

SPECIFICATION forming part of Letters Patent No. 662,122, dated November20, 1900.

Application filed May 28. 1900. .Serial No, 18,244. (No specimens.)

all whom it may cancer-m;

Be it known that we, ADOLF ISRAEL and RICHARD KOTHE, doctors ofphilosophy, chemists, residing at Elberfeld, Germany,

I and we hereby declare the following to be a clear and exactdescription of our invention.

In the two applications for Letters Patent 10 bearing Serial Nos. 11,239and 11,240, filed (assignors to the FARBENFABRIKEN OF ELBER- April 2,1900, we have described the produc- FELD COMPANY, of NewYork,)haveinvented tion of new urea and thio-urea compounds a new anduseful Improvement in Azo Dyes;

having the formula:

in which formula X means an atom of oxygen, which maybe replaced by anatom of sulfur.

Our present invention relates to the production of valuable new azocoloring-matters by causing two molecules of two different suitablediazo compounds to act on the said urea or thio-urea compounds. We pointout l l ox,

specifically that we intend to denote in the formula:

I 1 I I in which formula X means an atom of oxygen which may be replacedby an atom of sulfur, the groups N:NR and N:NR meaning two differentradicals of diazo compounds, such as diazobenzene, diazotoluene,diazoazobenzene, acetylamidodiazobenzene, beta-diazonaphthalene, or thelike, and are from reddish-brown to dark-brown powders having a metallicluster, soluble in water with from orange to red to bluish-red color,being insoluble in concentrated hydrochloric acid. They dye unmordantedcotton from orange to red shades which are of a remarkable fastness tolight.

In carrying out our new process practically we can proceed as follows,the parts being by weight: 6.65 parts of anilin are diazotized in theusual manner with the aid of twenty-eight parts of hydrochloric acid (of15 Baum) and five parts of sodium nitrite.

acid. The formation of the dyestuff will be finished after the solutionhas been stirred for one day. Subsequently forty parts of 65 sodiumcarbonate (Na GO are added to the reaction mixture in order to render italkaline. To the resulting liquid a diazo solu tion prepared from 10.7parts of acetylpara-phenylenedia'min with the aid of five 70 parts ofsodium nitrite and twenty-eight parts of hydrochloric acid (of 15 Baum)is slowly added. After being stirred for tered off, and dried. The newcolorinsr- 5 several hours the formation of the dye l matter thusobtained is the sodium salt of stuff will be complete. It is thenprecipian acid having most probably the following tated by the additionof common salt, filformula:

I OH

are employed. On using, for instance, one molecule of diazotized anilinand one molecule 25 of diazotized amidoazobenzene or one molecule ofdiazotized ortho-anisidin and one molecule of diazotizedbeta-naphthylamin bluishred dyestuffs are obtained.

Having now described out-invention and in what manner the same is to beperformed,what we claim as new, and desire to secure by Letters Patent,is-- 1. The process for producing new azo dyestuffs which processsconsists in first combin- 5 ing two molecules of two different diazocompounds with one molecule of an urea derivative having the generalformula:

and is a reddish-brown powder having a metallic luster, soluble in,water with a red color. It is insoluble in concentrated hydrochloricacid, while it is dissolved by concentrated sulfuric acid (of 66 Baum)with a bluishred color, which is changed into violet on the addition ofa small quantity of ice, while on the addition of a larger quantity ofice a brown precipitate is obtained.

The new coloring-matter dyes unmordanted cotton red shades, which arefast to acids and to light.

The process proceeds in an analogous manner if instead of the diazocompounds mentioned in the example other diazo compounds in whichformula 3 means an atom of oXy 2. The process for producing a new disazogen which may be replaced by an atom of dyestulf which process consist-sin first comsulfur, secondly precipitating the resulting bining onemolecule of diazotized anilin and .dyestuff by means of a suit-able saltand onemolecule of diazotized acetyl-para-phenyfinally isolating thesame from the reaction 1 mixture, substantially as hereinbeforedescribed.

lene-diamin with one molecule of carbonyldioxy-dinaphthylamin disulfonicacid havingin a free state the formula:

SO H

secondly precipitating the resulting dyestutf with the aid of a suitablesalt, and 3. The herein-described new azo dyestuffs finally isolatingthe same from the reacwhich are alkalinesalts of acids having most tionmixture, substantially as hereinbefore probably the general formula:

described.

X meaning in this formula an atom of oxygen which may be replaced by anatom of sulfur, the groups N:NR and N=NR meaning the radicals of twodifferent diazo compounds and which are from reddish-brown to dark-brownpowders having a metallic luster, soluble in water with from orange tored to bluish-red color,insolublein concentratedhydrochloricacid,dyeingnninordanted cotton from 4. The herein-describednew disazo dyeorange to red shades which are fast to light, stuff beingan alkaline salt of an acid having 5 substantially as hereinbeforedescribed. most probably the following formula which in the form of itssodium salt is a redshades Which are fast to acids and to light,dish-brown powder having a metallic luster, substantially ashereinbefore described. soluble in Water witha red color, insolublein Intestimony whereof we have signed our TO concentrated hydrochloric acid,being dist names in the presence of two subscribing wit- 2o solved byconcentrated sulfuric acid (of 66 nesses.

Bauin) with a bluish-red color which is ADOLF ISRAEL. changed intoviolet by the addition of asmall RICHARD KOTHE. quantity of ice, Whileon the addition of a Witnesses:

15 larger quantity of ice abrown precipitate is OTTO K6NIG,

obtained, dyeing umnordanted cotton red T. A. RITTERSHAUS.

